1. Field of the Invention
The invention relates to a cushioning unit for an oval-tracked exercise device, and more particularly, to a cushioning unit which protects the operator""s feet from shock caused by the reactive force of the treadles.
2. Description of the Related Art
U.S. Pat. No. 3,316,898 describes a xe2x80x9cREHABILITATION AND EXERCISE APPARATUSxe2x80x9d in the year of 1967 which includes an electric motor, a speed reducer, a small sprocket, a transmission chain, a transmission sprocket, a treadle crank, two elongated plates and two rollers to simulate the oval-tracked walking exercise with both feet of an operator.
Later, a few of improvements with similar functions and effects have been disclosed to continue and extend the principles and functions of the oval-tracked exercise. Therefore, this patent plays a significant part in the development of the exercise apparatuses.
However, this kind of exercise apparatus has drawbacks that both feet of the operator are moved by the machine rather than by his own will. Therefore, the operator has to adjust himself to the speed and the rhythm of the unit during the exercise session. Otherwise, his knee and ankle joints would be easily hurt. It""s more serious that this kind of injuries has no acute symptoms. The symptoms occur only when the injuries are serious.
It is a primary object of the present invention to take preventive measures to avoid the exercise injuries that are ignored by the unit suppliers for a long time. The invention includes a cushioning element for providing an appropriate cushioning effect when the treadles are located at the lowest position during the exercise session. Therefore, reactive forces of the treadles acting onto the operator""s feet are eliminated for preventing his feet from injuries.